Scanline alignment sensors

Abstract

An optical imaging system comprising: an optical assembly for producing a laser beam scanline at an imaging region; first and second photodetectors located at the imaging region at the first and second ends of a produced laser beam scanline; and a visual indicator system coupled to the first and second photodetectors to visually indicate detection of the first and second ends of the laser beam scanline.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This is a 111A application of Provisional Application Ser. No. 60 / 444,014, filed 31, Jan. 2003.FIELD OF THE INVENTION[0002]This invention relates in general to optical imaging systems and more particularly to visual aids for facilitating alignment of a laser beam scanline at an imaging region.BACKGROUND OF THE INVENTION[0003]In a Computed Radiography (CR) reader, the laser beam is scanned in a scanline over the surface of a storage phosphor screen by a reciprocating galvanometer mirror or polygon rotating mirror in a fast scan direction while the screen is transported under the scanline in a slow scan direction. To make the CR reader compact and manufacturable, a final fold mirror is placed in the optical path between an F-theta lens and the phosphor screen. The fold mirror introduces three degrees of freedom into the optical system. A coordinate system on the mirror has an x-axis in the plane of the mirror along the fast scan dimension o...

AI Technical Summary

Benefits of technology

[0011]1. Adjustment of the fold mirror can be made without direct observation of the laser beam, eliminating laser safety hazard and providing a repeatable and known alignment precision since the beam is aligned to precision slots in the CR reader.

Problems solved by technology

Also the process resulted in significant residual misalignment since the adjustment process was a subjective operator dependent alignment.

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